@seanheis1
I have just been around a long time, and as opposed to talking the talk, I have walked the walk ... but not that long. Still got another decade of work in me or so.
@dht4me
Frequency response and phase (which I said later on). Those two incorporate bandwidth which is an inadequate descriptor. Since we are talking about DACs, somewhat in isolation, but even if we were not, it does not matter, pre-amp loads are typically 10K-100K, non-reactive, and even $10 DACs have more than enough bandwidth, phase response and drive capability, again, technically more than the Audionote.
Jung, Swenson, etc. in the field of analog electronics, linear, are so far from the best minds. Competent perhaps, but if you are using what they say to determine what you are writing, then obviously at a system level ... well they should stick to analog.
What Audionote does in there power supplies or does not, really does not matter. All that matters is results. Measurements I have seen have shown more power supply harmonics then I would expect on any modern DAC, even <$100. Insisting on simple tube based output circuits makes it pretty hard to avoid that.
The regulators absolutely need to have the bandwidth in digital circuits and to conflate human hearing with digital circuits is sort of disingenuous.
Why? Tell me why, in full detail, and please explain what sort of result, say in picoseconds of jitter will result, and how much THD/IMD will result?
With any half way proper designed DAC, the DAC is being driven by a local clock either via buffer, USB, ASRC, etc. I can get exceptionally low phase noise with just some basic sense on the power supply side. It's amazing what a resistor, a ferrite bead, and a few ceramic capacitors can do. Since I have a stable clock, now I am down to logic edge speeds, or more specific, how fast I transition through the range of uncertainty, and that is going to be a few 100 picoseconds, now power supply noise will affect that, but if I am 0.1% noise on the power supply (and I can get better) then I am down in picoseconds worst case jitter, but because the edge speed is fast, and the important transitions actually very very few in audio, the odds of a noise peak being concurrent with a critical edge are low and hence RMS jitter contribution from a half way decent power architecture will have limited impact on performance. Of course, all of this assume the DAC itself has not implemented any techniques in the analog domain to reduce jitter. Most DACs chips do. What is in the Audionote does not, so it will be more sensitive again to design implementation.
We could talk about the DAC reference, but again, it is amazing what can be done with well chosen simple parts. There is a reason why companies buy test equipment. They know if they got it right or not. Not the right sound, which is much different, but they know if there are extraneous things happening they don't want to happen.
